class Warning(BaseException):
    pass
class Error(BaseException):
    def __init__(self,msg=None):
        BaseException.__init__(self,msg)
class InterfaceError(Error):
    pass
class DatabaseError(Error):
    def __init__(self,msg=None):
        Error.__init__(self,msg)

class DataError(DatabaseError):
    pass
class OperationalError(DatabaseError):
    pass
class IntegrityError(DatabaseError):
    pass
class InternalError(DatabaseError):
    pass
class ProgrammingError(DatabaseError):
    pass
class NotSupportedError(DatabaseError):
    def __init__(self,msg=None):
        DatabaseError.__init__(self,msg)
